Pivot centres



March 22, 1960 J. HADFIELD 2,929,662

PIVOT CENTRES Filed May 21, 1956 MFIGJ 2 Sheets-Sheet 1 J. HADFIELD Filed lay 21, 1956 2 Sheets-Sheet 2 nited rates Patent PIVOT CENTRES James Hadfield, Rorniley, Chester, England, assignor to Beyer Peacock & Company Limited, Manchester, England, a British company Application May 21, 1956, Serial No. 586,150

Claims priority, application Great Britain May 24, 1955 v Claims. (Cl. 308-137) This invention relates to pivot centres for articulated and bogie locomotives of all types and in particular diesel-electric, diesel-hydraulic, diesel-mechanical, gas turbine and electric locomotives.

The object of the invention is the provision of an improved pivot centre of the above character, which, amongst other advantages, can be applied, for example, to bogie pivot centres on electric or diesel locomotives without restricting the basic design of the bogies or imposing limitations on the space available for traction motors or gear boxes, or for access to such transmission units for inspection and maintenance.

The invention consists broadly of a pivot centre for articulated and bogie locomotives comprising a male member and a female member, said female member including a wearing element which is mounted so as to be movable towards the male member for taking up wear, wherein said wearing element is biased in the direction for taking up wear by means of a horizontally movable wedge which engages a surface of said wearing element and is itself biased by means of a long horizontal helical spring.

In order that the invention may be the more clearly understood two pivot centre constructions in accordance therewith will now be described, reference being made to the accompanying drawings wherein:

Figure 1 is a sectional elevation of one of said constructions the section being on line II of Figure 2.

Figure 2 is a sectional plan of the same, with the male pivot member removed the section being on line IIII of Figure 1.

Figure 3 is a sectional elevation of the other construction, the section being on line Ill-Ill of Figure 4.

Figure 4 is a sectional plan of the same, the section being on line IVlV of Figure 3.

Figure 5 is a cross section of the same, the section being on line V--V of Figure 4.

Referring first to Figures 1 and 2 the construction comprises a female pivot member 1, 2 which is mounted on the frame structure 3 of the bogie or truck or alternatively the swing bolster of the bogie or truck if such is provided, and a male pivot member 4 attached to the superstructure of the locomotive which extends downwards engaging the female member. The male member 4 has a flat bottom bearing plate 5 which rests on a corresponding flat bearing plate 6 at the bottom of the female member and supports the weight of the superstructure.

The male member 4 is also fitted with a renewable ring 7 in the form of a truncated cone, as in our prior Great Britain Patent No. 647,480, and the female member fl, 2 is machined to the same contour, this arrangement being designed to permit acertain amount of tilting ICE,

between the male and female members in both longitudinal and transverse directions.

The female member 1, 2 comprises a fixed bearing block 1 and an adjustable bearing block or wearing element 2 machined as mentioned above to the same conical contour as the ring 7 of the male member, with a clearance 8 between blocks 1 and 2 at each side to permit horizontal longitudinal movement of block 2 towards the male member as wear takes place.

The adjustable bearing block 2 is permanently biased towards the fixed block 1 by means ofa spring loaded wedge 9 and wear on the circumferential bearing surfaces of the male and female members is thus automatically taken up.

The wedge 9 moves in a horizontal direction. It has its geometrical axis at right angles to the direction of movement of the adjustable bearing block 2 and its two faces "are equally inclined in opposite direction with respect to said geometrical axis. One of said faces is in contact with the bearing block 2 and the other in contact with a fixed bearing block 10. The taper of the wedge 9 is so arranged that reversal of action can take place in response to the bearing blocks 1 and 2 being forced apart by the male member when the superstructure is being lowered into position on the bogies or trucks and also under conditions of tilting between the male and female members in a longitudinal direction. s

The wedge 9 is loaded by means of a long horizontal helical spring consisting of two component parts 11 and 12 arranged in series and connected by a bolt 13 passing through a longitudinal hole 27 in said wedge.

More particularly, thecomponent spring part 11 is in compression between a shoulder 28 countersunk in said hole in the wedge and a head 29 on the rear end of the bolt 13, a suitable washer 30 being provided between said spring part 11 and said head 29, and the component spring part 12 is in compression between a head 31 screwed on the forward end of said bolt and a fixed surface 32 beyond the forward end of the wedge, a

centres and the consequential shock loads and damage to the structure of the locomotive which can occur under these conditions. Also the pressure exerted by the bearing blocks 1 and 2 on the male member'creates a frictional resistance to rotation of the male member relative to the female member which greatly assists in preventing hunting or oscillation of the bogie or truck in the track.-

The female member 1, 2, the wedge 9 and the spring 11, 12 are housed in an oil-tight container which provides an oil bath for the working parts. This container comprises a casting 14 having a recess 35 which contains the female member 1, 2 and the wedge 9. A cover plate 15 covers said recess 35 and the male member projects into said recess through a hole in said cover plate, with a dust seal 16 between said male member and the edge of said hole.

The spring part 11 is also contained in said recess, but

the bolt 13 projects through a wall of said recess to the;

outside so that said spring part 12 is outside said casting.

An oil-tight cover 17 mounted'on the outside of said casting encloses'said spring part 12. A screwed plug 18 provides access for removal of spring partll and bolt 13.

Referring now to the construction illustrated in Figares" 31o 5, this is the sanreinprinciple' as that of Figtires 1 and "2 and like references have been employed for similar parts of the two constructions. In the case of Figures 3 to 5 however a long horizontal helical spring 19 is employed actuating the wedge 9 by means of a lever 20 and compression link 21'. The spring 19 is enclosed within a plunger 221which slides in a bored hole 34 formed in the casting 14' en thetside of the pivot centre remote from the wedge, and parallel to" a horifzont'al line at right tangles to the direction of travel of the': adjustable bearing block 2, ii.e. parallel to that diam- 'eter' of thepiv'ot centre which contains the clearances 8.

, ces'ses 23 and 35. The pivot pin 2,4 is disposed so that said lever snares-a mechanical advantage. This mechanical advantage-and the space available to accommodate the spring 19 permits'the employment of a spring of relatively light section and optimum deflection rate. 'All the' worlcing parts are enclosed in an oilba'th constituted bythe cavities 23 and'35 and the hole 34; The screwed plug 25- provides for removal of spring 19 and plunger 22 whilst the'oilti-ght cover '26 provides" for removal of the lever '20 after the cover plate 15 and pin 24 have been removed; The cover plate 15 covers both the cavity 23-and-t-he'rece'ss 35; e t

In both of the above embodiments the" fact that the slidable' bearing-block 2 can be forced to move away from the fixed bearing block 1- is of the greatest importance. For example, if excessive tilting movement should take place as mighthappen in the case of a derailment the sliding block 2 withdraws as required and pre vents binding'between the male; and female members which would otherwise-occur and relieves the supporting structure from excessive strains which would be caused bysuch binding. i

The conical form of the 'pivot' m'embers is also of great importance since it permits-a certain amount] of tilting bfoth longitudinal; and lateral directions--without bindmg and also tends to 'minimise the stress created by fsnatching when starting 'heavy trains'pilhis conical form in conjunction. with the fact that the slidable 'block 2 can he forced .b'ac'lc'dueto the reversible action of the wedge 9- is valso of value in facilitating-erection since the Q ghI-QQ the-superstructure as it is lowered int'oposinon automatically-forces the bearing blocks 1 and 2 apart duringient ry of :the male member. Thus the assembly does not require any slackening of the spring orany manipulation efcomponent-parts. V

B ot h embodiments are'particularly valuable for appncatlon to bogies o'rqtrue,k,s wherein design features a and space restrictions require a pivot centre entirely iconi Within mall sp e-in the vertical direction.

w be 3 t, i b th embodiments the loading P f is par llel to e s ome r cal'axis of the wedge,

bl i l a r gement is .sueh'that the extencof said spring" WW -.5 e h r: em; 9 S d W dge is :much less .thanthe 'e 5 p mg, and thus a compact design is achieved.

.li liainiz I r element for taking up wear, two component horizontal helical springs and a* coupling member, one of said springs biasing said wedge inv said given direction relative to one end of said'couplin'g member and the other of said springs biasing the other end of said coupling member relative to said housing to further bias said wedge in said given direction. t

2. A pivot centre for articulated locomotives and bogie locomotives, comprising a female pivot member mounted in a fixed housing anda male pivot member, said female pivot member including a wearing element which is-mounted so as to be'movable towards the male pivot member fortaking up wear, a horizontally movable wedge engaging a surface of said wearing element, a rod passing longitudinally through saidtwedge, a component helical spring in compression between said wedge and a shoulder on the portion of said rodwhich' extends beyondthe broad end of said wedge to urge the wedge in a given direction with respect to 'said red, the other end of said rod extending from the narrow end o'ftsaid wedge through an opening in said housing, and a'second component spring under compression intermediatesaid housing and a shoulder on said other'end of said rod for further urging said wedge in said given direction.

3. A pivot centre for articulated locomotives and bogie locomotives, comprising; a male pivot member and a female pivot member, said female pivottmember includ inga wearing element which is mounted so as to be movable towards the male pivot member for taking up wear, a horizontallyimovable wedge engaging a surface of said wearing, element, a rod'passing through a longitudinal bore hole'of'said wedge, acomponent helical spring in compression between a relativelyfixed part and a shoulder on the end ofvsaid rod which; extends beyond the narrow end of said wedge, and'a second component helical spring in compression betweena shoulder on the other end of said rod and a shoulder formed by counter sinking said bore hole from the broad end of said wedge, whereby said springs act in serieson said wedge to bias it in the direction for moving said wearing element for takingup wear. g

4; A pivot centre for articulated locomotives and bogie locomotives, comprisin'g'a femalepi'vot member, a male pivot member extending downwardly into said female pivot member, said female pivot member including a wearing element mounted so as to be movable towards the male pivot member for taking-up wear, a horizontally movable wedge engaging a surface of'said wearing element, two component horizontal helical springs, a rod coupling said springs, whereby said springs act in series on said 'wed'ge to bias it in the direction for moving said wearing element for taking up wear, said female pivot member, wedge springs and rod being housed in an oii tight container which provides an oil bath, and into whichsaid -malernember projects through an oil-tight seal.

5. A pivot centre for articulated locomotives and bogie locomotives, comprising a casting having a recess adapted to form an oil bath, a female pivot member mounted in said recess, a male pivot member extending downwardly into said female pivot member, said female pivot member including a 'wearinge'lement mounted so as to be 7 movable towards saidmale 'pivot'memberfor taking up 1- A pi-v'ot centre forarticulated locbmotives-and bogie iocomotiv'es, comprising a female pivot member mounted i l fi sd h usingaud a ma e -P 9 t m mber -said female 7PM! @5158; l il s a We ring e emeubwhich 3s e -d be mo ab e tewern the male pivot m -r we u Wear; a en anally :mova'ble wedge engaging a jsurface of said wearing element and wear, 1a horizontally movable Wedge mounted in said 7 recess and engaging a' surface of said wearing element,

a rod passing through a longitudinal borehole of said wedge and extending atits end beyond the narrow end of said wedgett'h-rongh a wall'ofsaid recess to the outside thereof, 3 component helical'spring outside said'wall and in compression between said'wa'll and a shoulder on the said end of said rod, a second component helical I springsin .compressionibetween said wedge and a shoulder on the :other end .o'fsaid rod, whereby said springs act in 'on said wedge to bias it in the direction for movin'grsaid wearingiel ement for taking up wear, a cover mounted onzthe outside :of said wallaand enclosing'the projecting rod portion and the first-named component FOREIGN PATENTS spring, and a cover for said recess through which the t. 1 male member pro ects 1n sealed relatlon. gig: 3222 a 1 References Cited in the file of this patent 5 518,251 Great Britain Feb. 21, 1940 140,217 Great Britain Feb. 13, 1951 UNITED STATES PATENTS 765,530 Germany Aug, 9, 1951 1,654,324 e 27, 1 145,295 Australia Feb. 20, 1952 2,151,603 l s th M81. 21, 1939 135 432 Sweden APR 29 1952 2,712,479 Hadfield July 5, 1955 m warm STATES rare orricn QETiFiCl-KTE 6F CORRECTION Patent No, 2,929,662 March 22, 1960 James Hadfield it is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected belowa In the grant, lines 2 and 3, for "assignor to Beyer Peacock 81 Company Limited, of Manchester, England, a British company," read assignor oi one-half to Beyer Peacock Company Limited, of Manchester, England, a British company, line 12, for Beyer Peacock 8: Company Limited, its successors" read James Hadfield, his heirs or assigns, and Beyer Peacock 8: Company Limited, its successors ----g in the heading to the printed specification, lines 3, 4, and 5, for "assignor to Beyer Peacock 82 Company Limited, Manchester, England, a British company read assignor of one-half to Beyer Peacock 8: Company Limited, Manchester, England, a British company Signed and sealed this 20th day of September 1960.

(SEAL) Attest:

ROBERT C WATSON Commissioner of Patents KARL H, AXLINE Attesting Officer 

